System information

If DRS is enabled and in fully automatic mode, DRS might move other virtual machines to further balance
the load across the cluster while Site Recovery Manager is powering on the recovered virtual machines. DRS
continues to balance all virtual machines across the cluster after Site Recovery Manager has powered on the
recovered virtual machines.
How Site Recovery Manager Interacts with Storage DRS or Storage
vMotion
You can use Site Recovery Manager when protecting virtual machines on sites that are configured for
Storage DRS or Storage vMotion if you follow certain guidelines.
The behavior of Storage DRS or Storage vMotion depends on whether you use Site Recovery Manager with
array-based replication or with vSphere Replication.
Using Site Recovery Manager with Array-Based Replication on Sites with
Storage DRS or Storage vMotion
You must follow the guidelines if you use array-based replication to protect virtual machines on sites that
use Storage DRS or Storage vMotion.
n
If your storage array supports consistency groups, Site Recovery Manager is compatible with vSphere
Storage DRS and vSphere Storage vMotion. You can use Storage DRS and Storage vMotion to move
virtual machine files within a consistency group that Site Recovery Manager protects. If your storage
array does not support consistency groups, you cannot use Storage DRS and Storage vMotion in
combination with Site Recovery Manager.
n
If you enable Storage DRS on the protection site, a datastore cluster must contain one and only one
consistency group. Do not include any datastore that does not belong to the consistency group in the
cluster. Placing multiple consistency groups into the same cluster might result in virtual machines being
lost during a recovery. This guideline also applies on the recovery site if Storage DRS is enabled on the
recovery site.
n
Do not use Storage DRS or Storage vMotion to move virtual machines regularly. Do not accept
recommendations to manually move virtual machines regularly. You can move virtual machines
occasionally, but excessive movement of virtual machines can cause problems. Moving virtual
machines requires the array to replicate virtual machines over the network, which takes time and
consumes bandwidth. When Storage DRS or Storage vMotion moves virtual machines, you might
encounter problems during a recovery:
n
If Storage DRS or Storage vMotion moves a virtual machine to a different consistency group within
the same protection group, there is a short period between Site Recovery Manager propagating the
new location of the virtual machine to the recovery site and the array replicating the changes to the
recovery site. In addition, there is another period during which the arrays replicate the source and
target consistency groups to a consistent state on the recovery site. While the array is propagating
all of the changes to the recovery site, disaster recovery of this virtual machine might fail.
n
If Storage DRS or Storage vMotion moves a virtual machine to a different protection group,
Site Recovery Manager generates a protection error for this virtual machine. You must unconfigure
protection of the virtual machine in the old protection group and configure protection of the virtual
machine in the new protection group. Until you configure protection in the new protection group,
planned migration or disaster recovery of this virtual machine fails.
n
Adding a disk to a protected virtual machine results in the same problems as for moving an entire
virtual machine. Site Recovery Manager does not prevent you from doing this, but if a virtual machine
contains an unreplicated disk and you do not exclude the disk from protection, powering on the virtual
machine fails after the move.
Chapter 9 Interoperability of Site Recovery Manager with Other Software
VMware, Inc. 93